The invention concerns a method for controlling a railway vehicle with a twin power plant, where each power plant comprises an internal combustion engine and a transmission unit, wherein a deviation of the set value and actual value of the drive torque and a prediction drive type are used to determine, by means of a traction manager, a set drive type in the sense of a single or double drive, a set operating point, and a set transmission stage for the transmission units.
In a railway vehicle with a twin power plant, the set drive torque is preset by a drive lever, which is then set by a train control unit as a default value for the internal combustion engines on a data bus, for example, a CAN bus. Due to the parallel drive, it is guaranteed that each internal combustion engine produces approximately the same drive power within the usual tolerances. When a twin power plant is used, the internal combustion engines are usually designed for maximum acceleration of the railway vehicle. During the acceleration process, the internal combustion engines are operated on the full-load curve of the engine performance map. After the maximum permissible vehicle speed has been reached, only the drive power needed to maintain the steady-state condition is still required. In the steady-state condition, therefore, the operating points of the internal combustion engines in the engine performance map lie in a range with distinctly higher fuel consumption. The problem in this respect is that higher fuel consumption sets in despite the lower power output.
A measure for improving this situation is disclosed by DE 1 455 052 OS, which describes a twin power plant and a control method for a railway vehicle. The twin power plant comprises a main diesel engine and an auxiliary diesel engine, a transmission, a generator, an electric controller, and an electric motor. The main diesel engine drives a generator, which in turn is connected by a shaft with the transmission. The auxiliary diesel engine is likewise connected with the transmission. The electric motor is arranged on the drive shaft of the transmission as an additional drive. The generator, the electric controller, and the electric motor describe a diesel electric drive path. In a first operating state corresponding to standstill of the railway vehicle, the main diesel engine is activated, while the auxiliary diesel engine and the transmission are deactivated. The current generated by the generator is used exclusively for preheating the train and for supplying power to other current consumers. In a second operating state corresponding to a low driving power requirement, the main diesel engine and the transmission are activated, while the auxiliary diesel engine remains deactivated. In its low and middle speed range, the main diesel engine drives the drive wheelsets via the transmission. To improve the engine efficiency, a portion of the engine output is transmitted parallel to the drive wheelsets via the electric drive connection, namely, via the generator, the controller and the electric motor. In a third operating state corresponding to a high power requirement, the main diesel engine and the auxiliary diesel engine are the common power source in the upper speed range up to the maximum speed. Here too, a portion of the engine output of the main diesel engine is transmitted by electric paths to the drive wheelsets to allow the main diesel engine to operate in the region of the most favorable fuel consumption.
Another measure is known from DE 814 904 PS, which discloses a twin power plant with two identical drivetrains. Each power plant comprises a diesel engine and a transmission system in the form of a generator and electric direct drive motors for driving the wheelsets. Both generators are mechanically connected by couplings on the output side with a reduction gear, which in turn drives the auxiliary equipment. Auxiliary equipment includes, for example, radiator fans, brake compressors, and the generators for generating the on-board supply voltage. The characteristic feature is that the auxiliary equipment that is essential for the operation can be optionally coupled with one or the other of the engines, which can be adjusted to constant total output, so that the internal combustion engine that is provided for driving the railway vehicle is operated in the region of favorable fuel consumption, while the other internal combustion engine drives the auxiliary equipment.
Although both of the measures described above result in reduced fuel consumption, they do not exhaust all possibilities for fuel savings.